my first metal gear solid experience was with MGS2. i was so captivated by the intense story lines and awesome game play mechanics i beat it several times, even on EXTREME (needless to say that was quite a feat).
MGS3 was just as compelling as the 2nd, and i simply loved the addition of camouflage. i never garnered the courage to attempt MGS3 on EXTREME, but i may some day in the future
after enjoying MGS2 and MGS3 so thoroughly i decided it would be a good idea to visit the roots of the metal gear solid series. so i played through the original Metal Gear Solid for PS and loved every minute of it. I also spent some time playing metal gear solid for Nintendo, but i had to retire from that because of increasing demands in school.
I have yet to play MGS4 because I don't have a PS3 and I don't have the time to commit myself to it yet. I feel empty right now because I haven't experienced its greatness yet...